(FILES) In this file photograph taken on August 29, 2020, Tanzania's incumbent President and presidential candidate of ruling…
FILE - Tanzania's President John Magufuli speaks at the Jamhuri Stadium in Dodoma, Tanzania, Aug. 29, 2020.

DAR ES SALAAM, TANZANIA - One week after Tanzania's general election in which President John Magufuli was declared the winner, the opposition is still demanding a rerun of the poll, which they said was full of irregularities. 

Police stopped opposition parties from holding protests Monday, a day after they arrested the head of the main opposition party and charged him with terrorism.  

Speaking to state media Sunday evening, Dar es Salaam regional police commander Lazaro Mambosasa accused the opposition of planning violence that included burning petrol stations and setting fire to citizens' cars. 

However, at a news conference Sunday, protest organizers said they were going to hold a peaceful demonstration.  

FILE - Freeman Mbowe, center, chairman of Chadema, Tanzania's main opposition party, arrives at Kisutu Magistrate Court in Dar es Salaam, Tanzania, March 10, 2020.

Also Sunday, police arrested the chairman of the main opposition Chadema Party, Freeman Mbowe, along with other party members, including a former member of Parliament and a former mayor of Dar es Salaam. All remained in police custody Monday. 

The opposition is vowing to hold protests until the election is repeated.  

Janeth Rithe, the national secretary for publicity and communication of the ACT Wazalendo Party, said the protest is nonstop, and no one can say it has failed. 

Another opposition party, the United Civic Front, said Sunday it rejects the election results.

Ibrahim Lipumba, chairman of the party, said party members will not participate in any election in Tanzania until a new constitution is obtained. 

The Electoral Commission, meanwhile, has shown no sign of heeding the calls for a new election. Magufuli is preparing for his inauguration later this week.